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Raptor and Corvid Use of Distribution Line Power Poles:. An Assessment of the Efficacy of Perch Deterrents. Previous Research. Man-made vertical structures are believed to lead to increased: Raptor and corvid visitation. Access to habitats.
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Raptor and Corvid Use of Distribution Line Power Poles: An Assessment of the Efficacy of Perch Deterrents
Previous Research • Man-made vertical structures are believed to lead to increased: • Raptor and corvid visitation. • Access to habitats. • Availability of perch, nesting, and roosting sites. • Foraging and predation efficiency.
Fragmentation • Divides suitable habitat. • Increases isolation of populations. • Abandonment of sites.
Study Objective • Test the efficacy of five types of perch deterrents on reducing the number of perching events of raptors and corvids.
Perch Deterrents One Fire Fly Two Fire Flies
Discouragers Cones (Kaddas) Triangles
Discouragers Spikes (Mini-zena) No treatment
Study (2007-2008) • 7.5 miles of power line with 84 poles.
Methods • Divided into 14 blocks of 6 poles. • Each block contained one of each discourager and a control. • Treatments and control were randomly assigned.
Survey Methods • Began mid-January, finish end of April. • Surveyed twice a day, five days a week. • Five minutes spent at starting point and each mile point. • Recorded species and numbers of individuals perched on the study poles.
Analysis • 1) Did the total count of perching events recorded by treatment and control in 2007 and 2008 differ by perch deterrent type and year? • 2) Did the total counts for each species on each type of deterrent and control in 2007 and 2008 differ?
Results 84 survey hours. 136 perching events. 168 survey hours. 253 perching events.
Results - 2007 • Golden eagles 77% of perching events. • Perching events did not differ by deterrent or control (p = 0.31). • Perching events did not differ by species.
Results - 2008 • Golden eagles 81% of perching events. • Perching events did not differ by deterrent or control (p = 0.15). • Perching events did not differ by species.
Discussion • Use cross arm deterrents • in combination with • insulator deterrents.
Acknowledgements • Advisor: Dr. Terry Messmer. • Committee: • Dr. Eugene Schupp, Dr. Chris Call, Dr. Fred Provenza, Dr. Tim Graham • Funders: • BLM and NRCS • Endangered Species Mitigation Fund • PacifiCorp • Jack H. Berryman Institute • Todd Black (and family) • Tammy Wallace (BLM) • Guy Wallace (UDWR) • Canyon Country Youth Corp. • Monticello/Dove Creek LWG • Private Landowners • Family and friends • My dog Jake